(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A sample of processed waste from a nuclear reactor contains 1.0*10^24 plutonium-239 atoms. The half life of plutonium-239 is 2.41*10^4 years.

a) How many plutonium-239 atoms will decay in the next 2.41*10^4 years?

b) Estimate the activity of the original sample.

2. Relevant equations

I guess that A=Ao(1/2)^t/(t*o.5)nwould be relevant, but really I don't see how. A= the decaying quantity remaining, which I know anyway, and nothing else that I could rearrange the equasion for will tell me the right answer.

3. The attempt at a solution

I managed to do a) alright, but I can't figure out b).

I can't really attempt the solution because I have no idea how. I know that the activity will be divided by 2 after each half life, but I don't know how to estimate the current activity to find the original. Please help me!!!

Thank you

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# Estimating activity of a radiocative sample

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